Exactly—data is the lifeline for that kind of muscle‑memory lift. Grab your GPS, heart‑rate monitor, and cadence sensor, then crunch the numbers: see where the runner’s velocity dips, where the heart rate spikes, and pinpoint the sweet spot. Adjust the beat to match those zones, ramp it up right before the final miles, and keep the tempo in that optimal range. No guesswork, just hard facts that turn a good run into a finish‑line sprint. If you’re not looking at the data, you’re basically playing music blindfolded—don’t do that.